- Department of Computer Science and Telecommunications,
TEI of Larissa
41110, Larissa
Greece - +302410684459
George Kakarontzas
UNIVERSITY OF THESSALY, GREECE, General of Larissa, Faculty Member
- TEI of Thessaly, Computer Science & Telecommunications, Faculty Memberadd
- Software Engineering, Software Reengineering, Component-Based Software Engineering (CBSE), Software Quality Engineering, Component Based Software Development, Software Reuse, and 6 moreGrid Computing, Software Metrics, Software Quality, Agile software development, Open Source Software, and Software Product Linesedit
- George Kakarontzas has a PhD with honors in Quality Assurance of Component-Based Software Systems from the Department... moreGeorge Kakarontzas has a PhD with honors in Quality Assurance of Component-Based Software Systems from the Department of Informatics, Aristotle University of Thessaloniki (Greece) and an MSc with Distinction in Object-Oriented Software Technology from the University of Brighton (UK). He is also a graduate of the Computer Science department of the Athens University of Business and Economics. George is an Associate Professor at the General Department of Larissa at the University of Thessaly, Greece, where he teaches Software Engineering, Software Quality and Compilers. In the past he has taught many related courses including Object-Oriented Programming (with Java and C#), Internet Programming with Java Enterprise Edition technologies and Distributed Systems. He publishes regularly in peer reviewed international journals and conferences in the area of software engineering and distributed computing.edit
Previous chapters in this book have dealt with Architecture Knowledge Management in traditional Closed Source Software (CSS) projects. This chapterwill attempt to examine the ways that knowledge is shared among participants in Free Libre... more
Previous chapters in this book have dealt with Architecture Knowledge Management in traditional Closed Source Software (CSS) projects. This chapterwill attempt to examine the ways that knowledge is shared among participants in Free Libre Open Source Software (FLOSS) projects and how architectural knowledge is managed w.r.t. CSS. FLOSS projects are organized and developed in a fundamentally different way than CSS projects. FLOSS projects simply do not develop code as CSS projects do. As a consequence, their knowledge management mechanisms are also based on different concepts and tools.
Research Interests:
An introduction to the Unified Modeling Language and Object-Oriented Software Development processes with case studies.
This work describes a research collaboration between universities and industry with the aim to provide a low-cost prototype based on Augmented Reality technologies, that assists with maintaining correct information in Warehouse Management... more
This work describes a research collaboration between universities and industry with the aim to provide a low-cost prototype based on Augmented Reality technologies, that assists with maintaining correct information in Warehouse Management Systems. The component interacts with the central server of an existing commercial WMS to provide up-to-date information on the actual state of the warehouse. The low-cost requirement restricts the solution to smartphones and other inexpensive equipment readily available, such as drones, as well as mostly Open Source Software. This requirement also introduces several interesting architectural issues that we discuss in this work. A prototype was built for the proposed architecture and several tests were carried out.
Research Interests:
Colin Atkinson, University of Mannheim, Germany Soren Auer, University of Leipzig, Germany William Chu, Tunghai University, Taiwan Joao M. Fernandes, University of do Minho, Portugal George Kakarontzas, Aristotle University of... more
Colin Atkinson, University of Mannheim, Germany Soren Auer, University of Leipzig, Germany William Chu, Tunghai University, Taiwan Joao M. Fernandes, University of do Minho, Portugal George Kakarontzas, Aristotle University of Thessaloniki, Greece Jingyue Li, Norwegian University of Science and Technology, Norway Neil Loughran, Lancaster University, UK Pornsiri Muenchaisri, Chulalongkorn University, Thailand Mikko Raatikainen, Helsinki University of Technology, Finland Salah Sadou, University of South Brittany, France Guifa Teng, Hebei Agricultural University, China Annual IEEE International Computer Software and Applications Conference
Research Interests:
Within the past decade, the advent of cloud computing in terms of infrastructure, technology stacks, availability of services and tooling, along with the gradual improvement of its market environment, has driven many organizations to... more
Within the past decade, the advent of cloud computing in terms of infrastructure, technology stacks, availability of services and tooling, along with the gradual improvement of its market environment, has driven many organizations to either consider or migrate many existing software systems to the cloud, either fully or partially. A common predicament in most cases, is the existence of a complex, monolithic application, potentially considered legacy at the time, that was not designed to be cloud-native and therefore requires a degree of redesign/reimplementation in order to benefit from cloud deployment. In such cases, the decomposition of the monolith to a set of loosely coupled, highly cohesive and self-contained microservices is a valid recommendation, provided that the organization is prepared to withstand the additional cost, in terms of human and financial resources, along with the unavoidable development overhead, which is inevitable during the early stages. However, the tendency of the tech world to embrace new trends and jump on hype trains for fear of obsoletion, has led to an excessive adoption of the microservices architecture (MSA), even in cases where such an architecture is not viable for the organization, or does not derive from any business requirements. This research focuses on establishing the position of a traditional monolith in the modern software architecture landscape and determine use cases that can still benefit from this paradigm, as well as use cases that could benefit from a partial or full transition to microservices architectures instead.
Research Interests:
This paper presents a novel requirements prioritization (RP) method which complements ad-hoc ranking approaches and ordinal scale-based RP techniques with capabilities of handing the vague and subjective perceptions that stakeholders have... more
This paper presents a novel requirements prioritization (RP) method which complements ad-hoc ranking approaches and ordinal scale-based RP techniques with capabilities of handing the vague and subjective perceptions that stakeholders have when they rank candidate requirements. To consider the indeterminacy and the lack of knowledge of stakeholders, the suggested method represents requirements' rankings with Intuitionistic Fuzzy Sets. The final priority list of requirements with respect to the prioritization criteria is derived by applying a multi-criteria decision method that is based on objective criteria weights. The larger the hesitation associated with a requirements ranking according to a chosen criterion, the smaller would be the weight of this criterion for the calculation of the final priority list. Through a case study, we demonstrate that the method is suitable for prioritizing requirements in an agile development process.1
Research Interests:
Research Interests:
Open source software is the product of a community process that in a single project may employ different development techniques and volunteers with diverse skills, interests and hardware. Reuse of OSS software in systems that will have to... more
Open source software is the product of a community process that in a single project may employ different development techniques and volunteers with diverse skills, interests and hardware. Reuse of OSS software in systems that will have to guarantee certain product properties is still complicated. The main reason is the many different levels of trust that can be placed on the various OSS sources and the lack of information for the impact that a reused OSS component can have on the system properties. A prerequisite for promoting widespread reuse of OSS software is certification at the component level in an affordable cost. This work addresses the main technical issues behind OSS component certification by formal and semiformal techniques, as well as the incentives that raised the need for the OPEN-SME European funded project. OPEN-SME introduces an OSS software reuse service for SMEs, in order to address the problem that OSS evolves by volunteers that follow different development proc...
Research Interests:
Research Interests:
Many researchers have suggested fuzzy-based methods to derive rankings of services based on the fuzzy degree that each service satisfies a set of weighted quality attributes. Most of these methods assume a closed set of candidate services... more
Many researchers have suggested fuzzy-based methods to derive rankings of services based on the fuzzy degree that each service satisfies a set of weighted quality attributes. Most of these methods assume a closed set of candidate services completely assessed. However, the candidate service set may include services which have not been fully assessed yet with respect to all quality attributes. Unassessed candidates introduce hesitation regarding the ranking of already evaluated services. In addition, even after services have been completely assessed, users may challenge the alleged assessments by disagreeing with them. Furthermore, users may suggest their preferences for quality attributes of services without providing numbers or ranges of numbers, but rather by providing characterizations of the relative importance of each attribute for their specific purposes. This paper suggests Intuitionistic Fuzzy Sets (IFSs) to handle these source s of uncertainty during services’ ranking based on their Quality of Service (QoS) attributes. IFS score functions are used to rank services with regard to each quality attribute. The final ranking can be derived by applying an objective method based on entropy weights for the quality attributes. In addition, users’ subjective selection of services based on preferences for the relative importance of quality properties is also discussed.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests: Information Systems, Computer Science, Distributed Computing, Grid Computing, Software Engineering, and 12 moreSoftware Components, Component-Based Software Engineering (CBSE), Software Agents, Clustering, Cluster Analysis, Software Agent, Grid, Geographic distribution, Indexation, Multidisciplinary Approach, Computational Grid, and Grid Scheduling
ABSTRACT Open Source Software (OSS) represents an extremely valuable resource that is reused systematically almost in every software project. The reuse of OSS components however is restricted to ready-made components and developers who... more
ABSTRACT Open Source Software (OSS) represents an extremely valuable resource that is reused systematically almost in every software project. The reuse of OSS components however is restricted to ready-made components and developers who want to reuse code that exists in OSS projects but is not offered as a black-box component often resort to copying existing code and adapting it in their projects. OPEN-SME is a European research project which aims at providing ready-to-use OSS components that originate from existing OSS projects but are not necessarily provided as such. In this work we describe the Component Adaptation Environment (COPE)tool that was developed in the context of the OPEN-SME project and enables software experts, called reuse engineers, to extract components from OSS projects, test them and provide test documentation, validate them with Model-Based Testing techniques, package them and upload them in a component repository for reuse.
Research Interests:
Big Data explosion is a phenomenon of the 21st century. Nowadays, more and more people are using the internet and creating new data regarding ideas, opinions, feelings or their views on a variety of topics and products. The micro-blogging... more
Big Data explosion is a phenomenon of the 21st century. Nowadays, more and more people are using the internet and creating new data regarding ideas, opinions, feelings or their views on a variety of topics and products. The micro-blogging platform Twitter is very popular and produces massive amount of data every fraction of a second and useful information may be generated from them. Sentiment analysis or opinion mining plays a major role in discovering all this information by analyzing these data and gain better insight of the public opinion on any subject in specific. In this paper a framework is proposed, built on top of the Hadoop ecosystem, for analyzing data from Twitter using a domain-specific Lexicon (in Greek).
Research Interests:
COMALAT (Competence Oriented Multilingual Adaptive Language Assessment and Training) project aims to strengthen the mobility of young workers across Europe, by improving job‐specific language competence tailored individually to particular... more
COMALAT (Competence Oriented Multilingual Adaptive Language Assessment and Training) project aims to strengthen the mobility of young workers across Europe, by improving job‐specific language competence tailored individually to particular needs. In this work we will concentrate on the COMALAT learning management system (LMS), which is a language learning system for Vocational Education and Training (VET). COMALAT LMS aims at providing learning material as an Open Educational Resource (OER) and is capable of self‐adapting to the needs of different learners. Each learner is treated individually in acquiring new language skills related to job‐specific competences. In addition, it is specifically tailored towards addressing competence areas, and therefore it is not a generic language learning platform. We discuss some technical details of the COMALAT platform and present the various aspects of system adaptability which tries to imitate the help provided by an instructor by observing the users’ strengths, weaknesses and progress in general, during the learning process. Also we discuss the digital e‐learning materials in COMALAT.
Research Interests:
Open Source Software (OSS) component certification is a prerequisite for the reuse of these components in diverse application domains. However, a particular challenge for software development Small and Medium Enterprises (SMEs) is the... more
Open Source Software (OSS) component certification is a prerequisite for the reuse of these components in diverse application domains. However, a particular challenge for software development Small and Medium Enterprises (SMEs) is the usually unacceptable high cost of certification which contradicts the economic benefits of OSS reuse. The OPEN-SME European funded project introduces an OSS software reuse service for SMEs in which SME Associations act as reuse service providers of OSS components for their member SMEs. In this work we describe the reuse and certification services of the OPEN-SME project for trustworthy OSS components, that aligns the benefits of OSS reuse with an effective reduction of the certification costs. Cost reduction is achieved with (a) The smaller scale of the certification subject (i.e. components instead of systems), (b) The use of a carefully selected toolset that increases automation and minimizes the human involvement as much as possible, and (c) The economies of scale introduced by the sharing of application domain specific components from a number of SMEs developing applications for the same application domain.
Research Interests:
ABSTRACT An efficient assessment of human resource competences, followed by the goal oriented analysis of the results, support the identification of the competence gaps in organizations and the allocation of resources towards identified... more
ABSTRACT An efficient assessment of human resource competences, followed by the goal oriented analysis of the results, support the identification of the competence gaps in organizations and the allocation of resources towards identified gaps. This paper presents the basic idea as well as the scientific and implementation results of the ComProFITS project as an innovative web-based platform for the evaluation of existing employees and the recruitment of new employees in organizations. The platform integrates research on the statistical assessment of competences, an innovative competence pyramid and many alternative methods of employee evaluation and recruitment. The initial version of the platform is being applied and used in the IT sector in a large organization in Spain with the goal of extending it to the Spanish and European wide enterprises in different sectors.
Research Interests:
ABSTRACT
Research Interests:
Research Interests:
ABSTRACT Emerging technologies such as Big Data and Cloud Computing in the field of information technology imposes further needs (requests) for professional competences in organizations and IT companies. The ultimate goal is to comply... more
ABSTRACT Emerging technologies such as Big Data and Cloud Computing in the field of information technology imposes further needs (requests) for professional competences in organizations and IT companies. The ultimate goal is to comply with industrial changes characterizedby adaptive solutions for fostering human-machine interactions. Here competence and job knowledge play a great role in organizations. This paper discusses the concept ofan adaptive competence profiling platform in the context of EU funded project ComProFITS. The main goal is (i) reinforcing competence analytics, and (ii) improving the quality of personnel selection and job performance in the IT sector. This project reflects the results of the research and development activities based on needs analysis with a Spanish IT company.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Abstract Over the past years, software development practices include open source code reuse. Since documentation gives little or no information about the system architecture, a prohibitive amount of effort is required to comprehend the... more
Abstract Over the past years, software development practices include open source code reuse. Since documentation gives little or no information about the system architecture, a prohibitive amount of effort is required to comprehend the source code and the overall ...
Research Interests:
Research Interests:
Research Interests:
Research Interests: Information Systems, Distributed Computing, Grid Computing, Software Engineering, Software Components, and 9 moreComponent-Based Software Engineering (CBSE), Software Agents, Clustering, Software Agent, Geographic distribution, Indexation, Multidisciplinary Approach, Computational Grid, and Grid Scheduling
Research Interests:
The massive amount of resources on computational grids raises the question of efficient resource discovery and selection. In this paper we present an agent-based approach to these two phases of a grid scheduling process. The approach is... more
The massive amount of resources on computational grids raises the question of efficient resource discovery and selection. In this paper we present an agent-based approach to these two phases of a grid scheduling process. The approach is based on client agents which act on behalf of grid users, and search for resources in a network of resource representatives that are registries of resource characteristics. After potentially suitable resources are discovered, client agents carry out negotiations directly with agents representing local resource management systems. This selection process first determines the willing resources with a contract-net protocol and then uses current load information and a more accurate post-discovery search to determine the optimum set of resources for the task in hand
Research Interests:
On large computational grids, performance is one of the main problems that has to be addressed but another important issue is the underlying interconnection network that has to be reliable in order to ensure the nodes' intercommunication... more
On large computational grids, performance is one of the main problems that has to be addressed but another important issue is the underlying interconnection network that has to be reliable in order to ensure the nodes' intercommunication and the migration of the appropriate load from one node to others. Reliability and performance are both influenced by the topology type of the underlying network. Fully connected networks for example provide better performance, the number of links however increases the cost of the system. In this paper, we considered these three factors, namely performance, reliability and cost, simulating performance for different network topologies and different reliability thresholds. The simulation results demonstrate that 1) regular topologies behave better than irregular topologies, and 2) the topology of the network is more influential to performance than the actual number of physical links.
Research Interests:
Research Interests:
Source code search engines assist the software development process by providing a way of searching for free source code in code repositories. Although their use is rather straightforward, there exist a few of them and the differences in... more
Source code search engines assist the software development process by providing a way of searching for free source code in code repositories. Although their use is rather straightforward, there exist a few of them and the differences in the way they index and provide access to their assets require considerable time and effort from the programmer to use them. In this paper, we present a federated open source code search engine that simultaneously asks, in real time, existing open source code search engine sites and detail the way we overcome the integration obstacles, by combining provided APIs, browser automation and web content extraction techniques.
Many researchers have suggested fuzzy-based methods to derive rankings of services based on the fuzzy degree that each service satisfies a set of weighted quality attributes. Most of these methods assume a closed set of candidate services... more
Many researchers have suggested fuzzy-based methods to derive rankings of services based on the fuzzy degree that each service satisfies a set of weighted quality attributes. Most of these methods assume a closed set of candidate services completely assessed. However, the candidate service set may include services which have not been fully assessed yet with respect to all quality attributes. Unassessed candidates introduce hesitation regarding the ranking of already evaluated services. In addition, even after services have been completely assessed, users may challenge the alleged assessments by disagreeing with them. Furthermore, users may suggest their preferences for quality attributes of services without providing numbers or ranges of numbers, but rather by providing characterizations of the relative importance of each attribute for their specific purposes. This paper suggests Intuitionistic Fuzzy Sets (IFSs) to handle these source s of uncertainty during services’ ranking based on their Quality of Service (QoS) attributes. IFS score functions are used to rank services with regard to each quality attribute. The final ranking can be derived by applying an objective method based on entropy weights for the quality attributes. In addition, users’ subjective selection of services based on preferences for the relative importance of quality properties is also discussed.
Research Interests:
Research Interests:
Research Interests:
Software Process Improvement (SPI) of Small Medium Enterprises (SMEs) is gaining momentum in software research and industry. It is recognized that in most countries software industry is composed of a scheme made up mainly of SMEs. This... more
Software Process Improvement (SPI) of Small Medium Enterprises (SMEs) is gaining momentum in software research and industry. It is recognized that in most countries software industry is composed of a scheme made up mainly of SMEs. This paper condenses efficient Software Engineering practices that will help a SME make tangible improvements in finite time. A practical and easily applied mechanism for SPI is suggested tailored in the needs, size and type of each SME. The main concept of this process involves creating a knowledge base that consists of information about three distinct improvement areas: experience, process and product area. This knowledge base is formed as an ontology that will provide further inference knowledge on the interrelationships of the information recorded. Such knowledge is exploited to define problematic areas and test alternative improvement solutions.
Research Interests:
OPEN-SME tries to bridge the gab between reusing complete OSS projects and the opportunistic reuse of small granules (e.g. classes).OPEN-SME provides two processes and three tools that hopefully will enable OSS component reuse for... more
OPEN-SME tries to bridge the gab between reusing complete OSS projects and the opportunistic reuse of small granules (e.g. classes).OPEN-SME provides two processes and three tools that hopefully will enable OSS component reuse for software development SMEs.